Highly Condensed and Super-Incompressible Be 2 PN 3 .

Although beryllium and its compounds show outstanding properties, owing to its toxic potential and extreme reaction conditions the chemistry of Be under high-pressure conditions has only been investigated sparsely. Herein, we report on the highly condensed wurtzite-type Be 2 PN 3 , which was synthesized from Be 3 N 2 and P 3 N 5 in a high-pressure high-temperature approach at 9 GPa and 1500 °C. It is the missing member in the row of formula type M 2 PN 3 (M = Mg, Zn). The structure was elucidated by powder X-ray diffraction (PXRD), revealing that Be 2 PN 3 is a double nitride, rather than a nitridophosphate. The structural model was further corroborated by 9 Be and 31 P solid-state nuclear magnetic resonance (NMR) spectroscopy. We present 9 Be NMR data for tetrahedral nitride coordination for the first time. Infrared and energy-dispersive X-ray spectroscopy (FTIR and EDX), as well as temperature dependent PXRD complement the analytical characterization. Density functional theory (DFT) calculations reveal super-incompressible behavior and the remarkable hardness of this low-density material. The formation of Be 2 PN 3 through a high-pressure high-temperature approach expands the synthetic access to Be-containing compounds and may open access to various multinary beryllium nitrides.